Picture frame corner



FIG. 1 is a perspective view of a picture frame corner, showing my new design, the broken lines are for environmental purposes only and form no part of the claimed design;

FIG. 2 of a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a picture frame corner, as shown and described. 